Audible altimeter for parachutists

• US 5,638,059 A
• Filed: 01/29/1996
• Issued: 06/10/1997
• Est. Priority Date: 01/29/1996
• Status: Expired due to Fees

• Current Assignee: George Pilkington
• Original Assignee: George Pilkington
• Inventors: Pilkington, George
• Primary Examiner(s): Mullen, Thomas
• Assistant Examiner(s): Lee, Benjamin C.
• Application Number:
  US08/591,966
• Time in Patent Office: 498 Days
• Field of Search: 340/970, 340/977, 340/963, 340/971, 340/611, 244/142, 244/147, 244/187, 244/149, 244/150, 73/384, 73/385, 73/386, 73/179, 364/433, 116/266, 116/268, 116/276
• US Class Current: 340/970
• CPC Class Codes: G01C 5/06 by using barometric means

Abstract

The invention relates to an audible altimeter for use by parachutists. The altimeter comprises a sensor means 6 for sensing ambient air pressure, an electronic processor 5, a sounder device 4 and control buttons 2,3. The electronic processor 5 is programmed to determine the height of the altimeter above ground level and send said signals to said sounder device 4 during the parachutist'"'"'s descent causing said sounder device 4 to emit a first audible signal at a first predetermined height above ground level and a second audible signal at a second predetermined height.

Claims

1. An altimeter for use by parachutists, the altimeter comprising:

a sensor means for sensing ambient air pressure and generating a signal P representing the sensed pressure;

a first digital electronic memory M_GL for storing a value P_GL determined from the ambient air pressure signal P at ground level, and means for entering said value P_GL into said memory;

a digital electronic processor means connected to said sensor means and said first memory M_GL and programmed to determine from said signal P and said value P_GL the height H_AGL of the altimeter above ground level;

a second digital electronic memory M_BO for storing a value H_BO representing a desired break off height and means for entering a value into said second memory;

a third digital electronic memory M_SDH for storing a value H_SDH representing a predetermined standard deployment height, and

a sounder device connected to said digital electronic processor so as to receive a signal therefrom and to emit an audible signal when said signal is received;

said digital electronic processor being connected to said second and third memories M_BO and M_SDH and programmed to compare said height H_AGL with said values H_BO and H_SDH and to send signals to said sounder device causing said sounder device to emit a first audible signal when said height H_AGL corresponds to the value H_BO and a second audible signal when the sensed height H_AGL corresponds to the value H_SDH.

2. An altimeter as claimed in claim 1, wherein the digital electronic processor means comprises a programmable interface controller.

3. An altimeter according to claim 1, wherein said means for entering said value H_BO into said memory M_BO comprises a manually operable switch means.

4. An altimeter according to claim 1, wherein said means for entering said value P_GL into said memory M_GL comprises a manually operable switch means.

5. An altimeter according to claim 1, wherein said digital electronic processor means is programmed to enter said value P_GL into said memory M_GL at predetermined time intervals.

6. An altimeter according to claim 1, wherein said digital electronic processor means is programmed to send a signal to the sounder device causing the device to emit an audible signal when, during the ascent, the sensed height H_AGL exceeds the value H_BO.

7. An altimeter according to claim 1, wherein said altimeter includes a source of electrical power and said digital electronic processor means is programmed to monitor the state of charge of said source of electrical power and to send a signal to activate said sounder device when said state of charge falls below a predetermined value.

8. An altimeter according to claim 1, wherein said altimeter includes a fourth digital electronic memory M_MDH for storing a value H_MDH representing a predetermined minimum deployment height, and said digital electronic processor is connected to said fourth memory M_MDH and programmed to compare said height H_AGL with said value H_MDH and to send a signal to activate said sounder device when said height H_AGL corresponds to the value H_MDH.

9. An altimeter according to claim 1, wherein said digital electronic processor means is programmed to monitor the rate of descent and to disable said means for entering said values H_BO and P_GL into said memories M_BO and M_GL when the rate of descent exceeds a predetermined value.

10. An altimeter according to claim 1, wherein said digital electronic processor means is programmed to monitor the rate of descent and to discontinue sending signals to activate said sounder device when the rate of descent falls below a predetermined value.

11. An altimeter according to claim 1, said altimeter being switchable between a stand-by state, in which power consumption is reduced, and an active state, in which the pressure signal P is constantly monitored, said digital electronic processor means being programmed to switch the altimeter to said active state when a rapid increase in altitude is sensed.

12. An altimeter according to claim 11, wherein said digital electronic processor means is programmed to send a signal to the sounder device causing the device to emit an audible signal when the altimeter switches from the stand-by state to the active state.

13. An altimeter according to claim 11, wherein said digital electronic processor means is programmed to sense completion of the descent and to switch the altimeter from the active state to the stand-by state after completion of the descent is sensed.

14. An altimeter according to claim 11, wherein said digital electronic processor means is programmed to sense the pressure signal P at predetermined time intervals when in the stand-by state and to switch the altimeter from the stand-by state to the active state in accordance with sensed changes in the pressure signal P.

15. An altimeter according to claim 14, wherein said digital electronic processor means is programmed to switch the altimeter from the stand-by state to the active state when the difference between the pressure signal P and the stored value P_GL exceeds a predetermined limit.